Final answer:
In financial auditing, a control deficiency is considered a material weakness if there is a reasonable possibility of a material misstatement in the financial statements that will not be prevented or detected and corrected promptly. A reasonable possibility indicates a likelihood higher than remote but lower than likely.
Step-by-step explanation:
To determine at what level a probability of material misstatement is required for a control deficiency to be considered a material weakness, it is vital to understand the context of financial auditing. A material weakness in internal control over financial reporting is a deficiency, or a combination of deficiencies, in internal control such that there is a reasonable possibility that a material misstatement of the entity's financial statements will not be prevented, or detected and corrected, on a timely basis. The term 'reasonable possibility' indicates that the likelihood can be either reasonably possible or probable. Although there is no quantifiable level of probability set in stone, a reasonable possibility is often interpreted as a higher likelihood than remote but lower than likely.